/*
 * threadsafe_unordered_map.h
 *
 *  Created on: 2016年7月26日
 *      Author: guyadong
 */

#ifndef COMMON_SOURCE_CPP_THREADSAFE_UNORDERED_MAP_H_
#define COMMON_SOURCE_CPP_THREADSAFE_UNORDERED_MAP_H_
#include <unordered_map>
#include <memory>
#include <utility>
#include "RWLock.h"

namespace gdface {
inline namespace mt{
/*
 * 基于std::unordered_map实现线程安全map
 * 禁止复制构造函数
 * 禁止复制赋值操作符
 * 允许移动构造函数
 * 禁止移动赋值操作符
 * */
template<typename _Key, typename _Tp,
	typename _Hash = std::hash<_Key>,
	typename _Pred = std::equal_to<_Key>,
	typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
class threadsafe_unordered_map{
private:
	std::unordered_map<_Key,_Tp,_Hash,_Pred,_Alloc> map;
	mutable RWLock lock;
public:
	using map_type=std::unordered_map<_Key,_Tp,_Hash,_Pred,_Alloc>;
	using key_type=typename map_type::key_type;
	using mapped_type=typename map_type::mapped_type;
	using value_type=typename map_type::value_type;
	using hasher=typename map_type::hasher;
	using key_equal=typename map_type::key_equal;
	using allocator_type=typename map_type::allocator_type;
	using reference=typename map_type::reference;
	using const_reference=typename map_type::const_reference;
	using pointer=typename map_type::pointer;
	using const_pointer=typename map_type::const_pointer;
	using iterator=typename map_type::iterator;
	using const_iterator=typename map_type::const_iterator;
	using local_iterator=typename map_type::local_iterator;
	using const_local_iterator=typename map_type::const_local_iterator;
	using size_type=typename map_type::size_type;
	using difference_type=typename map_type::difference_type;

	threadsafe_unordered_map()=default;
	threadsafe_unordered_map(const threadsafe_unordered_map&)=delete;
	threadsafe_unordered_map(threadsafe_unordered_map&&)=default;
	threadsafe_unordered_map& operator=(const threadsafe_unordered_map&)=delete;
	threadsafe_unordered_map& operator=(threadsafe_unordered_map&&)=delete;
	explicit threadsafe_unordered_map(size_type __n,
			    const hasher& __hf = hasher(),
			    const key_equal& __eql = key_equal(),
			    const allocator_type& __a = allocator_type()):map(__n,__hf,__eql,__a){}
	template<typename _InputIterator>
	threadsafe_unordered_map(_InputIterator __first, _InputIterator __last,
			      size_type __n = 0,
			      const hasher& __hf = hasher(),
			      const key_equal& __eql = key_equal(),
			      const allocator_type& __a = allocator_type()):map(__first,__last,__n,__hf,__eql,__a){}
	threadsafe_unordered_map(const map_type&v): map(v){}
	threadsafe_unordered_map(map_type&&rv):map(std::move(rv)){}
	explicit
	threadsafe_unordered_map(const allocator_type& __a):map(__a){}
	threadsafe_unordered_map(const map_type& __umap,
			    const allocator_type& __a):map(__umap,__a){}
	threadsafe_unordered_map(map_type&& __umap,
			    const allocator_type& __a):map(std::move(__umap),__a){}
	threadsafe_unordered_map(std::initializer_list<value_type> __l,
			    size_type __n = 0,
			    const hasher& __hf = hasher(),
			    const key_equal& __eql = key_equal(),
			    const allocator_type& __a = allocator_type()):map(__l,__n,__hf,__eql,__a){}
	threadsafe_unordered_map(size_type __n, const allocator_type& __a)
	      : threadsafe_unordered_map(__n, hasher(), key_equal(), __a){}
	threadsafe_unordered_map(size_type __n, const hasher& __hf,
			    const allocator_type& __a)
	      : threadsafe_unordered_map(__n, __hf, key_equal(), __a){}
	template<typename _InputIterator>
	threadsafe_unordered_map(_InputIterator __first, _InputIterator __last,
			      size_type __n,
			      const allocator_type& __a):map(__first,__last,__n,__a){}
	template<typename _InputIterator>
	threadsafe_unordered_map(_InputIterator __first, _InputIterator __last,
			      size_type __n, const hasher& __hf,
			      const allocator_type& __a)
		  : threadsafe_unordered_map(__first, __last, __n, __hf, key_equal(), __a){}
	threadsafe_unordered_map(std::initializer_list<value_type> __l,
			    size_type __n,
			    const allocator_type& __a)
	      : threadsafe_unordered_map(__l, __n, hasher(), key_equal(), __a){}
	threadsafe_unordered_map(std::initializer_list<value_type> __l,
			    size_type __n, const hasher& __hf,
			    const allocator_type& __a)
	      : threadsafe_unordered_map(__l, __n, __hf, key_equal(), __a){}
	bool  empty() const noexcept{
		auto guard=lock.read_guard();
		return map.empty();
	}
	size_type size() const noexcept{
		auto guard=lock.read_guard();
		return map.size();
	}
	size_type  max_size() const noexcept{
		auto guard=lock.read_guard();
		return map.max_size();
	}
	 iterator begin() noexcept{
		 auto guard=lock.write_guard();
		 return map.begin();
	 }
	 const_iterator begin() const noexcept{
		 auto guard=lock.read_guard();
		 return map.begin();
	 }
	 const_iterator cbegin() const noexcept{
		 auto guard=lock.read_guard();
		return map.cbegin();
	 }
	 iterator end() noexcept{
		 auto guard=lock.write_guard();
		 return map.end();
	 }
	 const_iterator end() const noexcept{
		 auto guard=lock.read_guard();
		 return map.end();
	 }
	 const_iterator cend() const noexcept{
		 auto guard=lock.read_guard();
		 return map.cend();
	 }
	 template<typename... _Args>
		std::pair<iterator, bool>
		emplace(_Args&&... __args){
		 auto guard=lock.write_guard();
		 return map.emplace(std::forward<_Args>(__args)...);
	 }
     template<typename... _Args>
	iterator
	emplace_hint(const_iterator __pos, _Args&&... __args){
    	 auto guard=lock.write_guard();
    	 return map.emplace_hint(__pos, std::forward<_Args>(__args)...);
     }
     std::pair<iterator, bool> insert(const value_type& __x){
    	 auto guard=lock.write_guard();
    	 return map.insert(__x);
     }
     template<typename _Pair, typename = typename
     	       std::enable_if<std::is_constructible<value_type,
     						    _Pair&&>::value>::type>
     	std::pair<iterator, bool>
     	insert(_Pair&& __x){
    	 auto guard=lock.write_guard();
    	 return map.insert(std::forward<_Pair>(__x));
     }
     iterator
	 insert(const_iterator __hint, const value_type& __x) {
    	 auto guard=lock.write_guard();
         return map.insert(__hint, __x);
     }
     template<typename _Pair, typename = typename
     	       std::enable_if<std::is_constructible<value_type,
     						    _Pair&&>::value>::type>
    iterator
    insert(const_iterator __hint, _Pair&& __x){
    	auto guard=lock.write_guard();
    	return map.insert(__hint, std::forward<_Pair>(__x));
    }
    template<typename _InputIterator>
    void
    insert(_InputIterator __first, _InputIterator __last){
    	auto guard=lock.write_guard();
    	map.insert(__first, __last);
    }
    void insert(std::initializer_list<value_type> __l){
    	auto guard=lock.write_guard();
    	map.insert(__l);
    }
    iterator  erase(const_iterator __position){
    	auto guard=lock.write_guard();
    	return map.erase(__position);
    }
    iterator erase(iterator __position){
    	auto guard=lock.write_guard();
    	return map.erase(__position);
    }
    size_type erase(const key_type& __x){
    	auto guard=lock.write_guard();
    	return map.erase(__x);
    }
    iterator erase(const_iterator __first, const_iterator __last){
    	auto guard=lock.write_guard();
    	return map.erase(__first, __last);
    }
    void clear() noexcept{
    	auto guard=lock.write_guard();
    	map.clear();
    }
    void swap(map_type& __x) noexcept( noexcept(map.swap(__x._M_h)) ){
    	auto guard=lock.write_guard();
    	map.swap(__x._M_h);
    }
    hasher hash_function() const{
    	auto guard=lock.read_guard();
    	return map.hash_function();
    }
    key_equal key_eq() const{
    	auto guard=lock.read_guard();
    	return map.key_eq();
    }
    iterator find(const key_type& __x){
    	auto guard=lock.write_guard();
    	return map.find(__x);
    }
    const_iterator find(const key_type& __x) const{
    	auto guard=lock.read_guard();
    	return map.find(__x);
    }
    size_type count(const key_type& __x) const {
    	auto guard=lock.read_guard();
    	return map.count(__x);
    }
    std::pair<iterator, iterator> equal_range(const key_type& __x){
    	auto guard=lock.write_guard();
    	return map.equal_range(__x);
    }
    std::pair<const_iterator, const_iterator>
    equal_range(const key_type& __x) const{
    	auto guard=lock.read_guard();
    	return map.equal_range(__x);
    }
    mapped_type& operator[](const key_type& __k){
    	auto guard=lock.write_guard();
    	return map[__k];
    }
    mapped_type& operator[](key_type&& __k){
    	auto guard=lock.write_guard();
    	return map[std::move(__k)];
    }
    mapped_type& at(const key_type& __k){
    	auto guard=lock.write_guard();
    	return map.at(__k);
    }
    const mapped_type& at(const key_type& __k) const{
    	auto guard=lock.read_guard();
    	return map.at(__k);
    }
    size_type bucket_count() const noexcept{
    	auto guard=lock.read_guard();
    	return map.bucket_count();
    }

    size_type max_bucket_count() const noexcept{
    	auto guard=lock.read_guard();
    	return map.max_bucket_count();
    }
    size_type bucket_size(size_type __n) const{
    	auto guard=lock.read_guard();
    	return map.bucket_size(__n);
    }
    size_type bucket(const key_type& __key) const{
    	auto guard=lock.read_guard();
    	return map.bucket(__key);
    }
    local_iterator  begin(size_type __n) {
    	auto guard=lock.write_guard();
    	return map.begin(__n);
    }
    const_local_iterator  begin(size_type __n) const {
    	auto guard=lock.read_guard();
    	return map.begin(__n);
    }
    const_local_iterator cbegin(size_type __n) const{
    	auto guard=lock.read_guard();
    	return map.cbegin(__n);
    }
    local_iterator end(size_type __n) {
    	auto guard=lock.write_guard();
    	return map.end(__n);
    }
    const_local_iterator end(size_type __n) const{
    	auto guard=lock.read_guard();
    	return map.end(__n);
    }
    const_local_iterator cend(size_type __n) const{
    	auto guard=lock.read_guard();
    	return map.cend(__n);
    }
    float load_factor() const noexcept{
    	auto guard=lock.read_guard();
    	return map.load_factor();
    }
    float max_load_factor() const noexcept{
    	auto guard=lock.read_guard();
    	return map.max_load_factor();
    }
    void max_load_factor(float __z){
    	auto guard=lock.write_guard();
    	map.max_load_factor(__z);
    }
    void rehash(size_type __n){
    	auto guard=lock.write_guard();
    	map.rehash(__n);
    }
    void reserve(size_type __n){
    	auto guard=lock.write_guard();
    	map.reserve(__n);
    }

    /*
     * 新增加函数
     * 在map中查找指定的key,bool值返回是否找到
     * 返回true时,将value中置为找到的值
     * */
    bool find(const key_type& __x, mapped_type &value) const{
    	auto guard=lock.read_guard();
    	auto itor=map.find(__x);
    	auto found=itor!=map.end();
    	if(found)
    		value=itor->second;
    	return found;
    }
    /*
     * 新增加函数
     * 返回读取锁的RAII对象
     * 在对map进行读取操作时应该先调用此函数
     * */
    raii read_guard()const noexcept{
    	return lock.read_guard();
    }
    /*
     * 新增加函数
     * 返回写入锁的RAII对象
     * 在对map进行写入操作时应该先调用此函数
     * */
    raii write_guard()noexcept{
    	return lock.write_guard();
    }
    /*
     * 新增加函数
     * 如果指定的key不存在，则增加key->value映射
     * 如果指定的key存在返回key映射的值,否则返回value
     * */
    mapped_type insertIfAbsent(const key_type& key,const mapped_type &value){
    	auto guard=lock.write_guard();
    	auto itor=map.find(key);
    	if (itor==map.end()){
			map.insert(value_type(key, value));
			return value;
    	}
    	return itor->second;
    }
    /*
     * 新增加函数
     * 如果指定的key存在，则用value替换key映射的值,返回key原来映射的值
     * 否则返回nullptr
     * */
    std::shared_ptr<mapped_type> replace(const key_type& key,const mapped_type &value){
    	auto guard=lock.write_guard();
    	if (map.find(key)!=map.end()){
			map.insert(value_type(key, value));
			return std::make_shared<mapped_type>(value);
    	}
    	return std::shared_ptr<mapped_type>();
    }
    /*
     * 新增加函数
     * 如果存在key->value映射，则用newValue替换key映射的值,返回true
     * 否则返回false
     * */
    bool replace(const key_type& key,const mapped_type &value,const mapped_type &newValue){
    	auto guard=lock.write_guard();
    	auto itor=map.find(key);
    	if (itor!=map.end()&&itor->second==value){
			map.insert(value_type(key, newValue));
			return true;
    	}
    	return false;
    }
    template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1,
	       typename _Alloc1>
      friend bool
    operator==(const threadsafe_unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&,
		 const threadsafe_unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&);
};
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator==(const threadsafe_unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
	       const threadsafe_unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{
	auto guardx=__x.lock.read_guard();
	auto guardy=__y.lock.read_guard();
	return __x.map._M_equal(__y.map);
}
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator!=(const threadsafe_unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
	       const threadsafe_unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{
	auto guardx=__x.lock.read_guard();
	auto guardy=__y.lock.read_guard();
	return !(__x == __y);
}
}/* namespace mt */
}/* namespace gdface */
#endif /* COMMON_SOURCE_CPP_THREADSAFE_UNORDERED_MAP_H_ */
